Hanbin and Jihye are soul mates who live in a very special universe where one begins to see color when they meet their other half. However, a destined love like this comes with a catch: only one person of the pair will know, and it is up to them to let the other find out. While Hanbin's vision is monochrome, Jihye lives a vividly pigmented life.

While Hanbin believes he has a lifetime to find his true love, time is running out for Jihye. Will Hanbin break the grayscale and see the world in color before it's too late?